Metal-bending device



Jan. 2, 1923, 11,440,982

w. e. GRAHAM.

METAL BENDING DE E. F|LED AUG. 24. I

gin/21am Patented Jan. 2, 1%23.

PATENT @FFEUE.

WILLIAJVI E. GRAHAM, OF LOUISVILLE, KENTUCKY.

BIE'IAL-BENDING DEVICE.

Application filed August .34, 1921.

T 0 aZZ whom it may concern Be it known that 1, WILLIAM E. GRAHAM, acitizen of the United States, residing at Louisville, in the county ofJefferson and State of Kentucky, have invented certain new and usefulImprovements in Metal- Bendino' Devices, of which the following is aspecification.

My invention relates to metal bending and forming devices, and moreparticularly to the forming jaws and the method of operating the same.

My object is to provide a device of this character which will be strong,si1nple and durable, and which will deliver a pmvorful clamping force onthe metal operated upon, so as to giv a perfect form thereto.

Minor objects will appear in the subjoined description.

A leading feature of the invention consists of a pair of jaws hingedtogether with their pivot point mounted for guided reciprocatingmovement in a stationary member, said jaws being provided between theirends with rollers taking into'curved slots in the stationary member, soarranged relatively to the line of reciprocating movement of the jawsthat the jaws are forced together when they are moved in one direction,and opened when they are moved in the other. v I i The inventionconsists in certain novel features of construction and arrangement ofparts, as will be hereinafter described and claimed, reference being hadto the accompanying drawings, in which;-

' Flg. 1 is a plan view showing the jaws open in position to receive apiece of metal to be bent. a

Fig. 2 is a horizontal section taken through the jaws showing therelative posi tion of the parts when the bending operation has just beencompleted.

Fig. 3 shows the parts in the same position as shown in Fig. 2, with aslight modification or addition to the curved jaw-operating slots,'oneof the jaws being broken away to show one of the slots complete.

Fig. 4 is a broken side elevation showing a part of the supportingtable, with the parts in the position illustrated in Fig. 1, and with apipe hanger (which has just been completed) falling through an openinginv the table.

Serial No. 495,004.

Fig. 5 is a side elevation of the forming jaws, showing the partsconnected directly thereto and moving therewith; and,

Fig. 6 is an end view of the dove-tailed guide block of the bendingjaws.

The numeral 1 indicates a strong table on which my device is supported.The bending jaws 2 are mounted on top of this table and are formed oftwo similar pieces hinged together by the pivot 8, which extends downinto a dovetailed guide block 4, which in turn, moves back and forth ina correspondingly shaped guideslot 5 in the table 1.

The jaws 2 are also provided on their under sides. preferably aboutmidway bc tween their ends, with frictional rollers 6 which are receivedinto the outer ends of curved slots 7 in the supporting table when thejaws are open as shown in Fig. 1. These slots 7 are so disposedrelatively to the pivot 3 and the guide slot 5 and the friction rollers6, that as the pivot 3 with the guide block 4: is moved to the right,the rollers 6 will travel toward the left in the slots 7 and close thejaws 2.

The forming head 8 of my device rests on top of the table 1 in the sameplane with the aws 2, and is rigidly secured at its upper side to thethrust bar 9, which has guided longitudinal movement between the rollers10, which are suitably supported on blocks 11 rigidly mounted on thetable 1. These rollers 10 have flanges 1O slightly overreach ing the topof the thrust'bar 9 to hold the same against accidental upward movement.

The diameter of the forming head 8 and the inner diameter of the jaws 2when closed, are of just sufficient difference to receive between thetwo around the forming head the piece of metal to. be operated upon.

The reciprocating plunger 9, carrying the forming head 8, is connectedwith suitable machinery (not shown) for moving it back and forth asuitable distance into and out of engagement with the bending jaws 2, asis usual with machines of this character.

When the hinged ends of the jaws 2 are moved outwardly in the slot 5 toclose the jaws, the spring 12 is compressed, so that as the forming head8 makes its return movement, the jaws are opened bythe action of saidspring, which may be connected to the jaws in a variety of ways, butwhich for purposes of easy illu tration, is here shown as held in theslot 5 by a late on the edge otthe table, and a pm let extending fromthe guide block 4t into the end ofsa id spring, the plate 13 having abore through which said pin may project when the springv is fullycompressed.

The operation of my device is as follows i When the parts of the deviceare brought into position to open the jaws, as shown in Fig. 1, thepiece of metal 15 to be bent, is placed in the ordinary way between thejaws, and the forming head 8 carried by the plunger 9 is moved inwardlyinto engagement with the piece of metal 15 at its mid dle portion, andas the forming head moves the hinged ends of the jaws outwardly alongthe slot 5, the rollers 6 travel inwardly in the curved slots 7 till thejaws 2 are closed and the piece of metal bent into form around theforming head, as shown in Fig. 2, at which point the forming head beingcarried on the plunger 9, begins its receding movement, carrying thepiece of formed metal around it, till said forming head is brought overthe opening 17 in the table when the piece of formed metal 16 (which inthe present instance is a pipe hanger) drops off the forming head 8 anddown through said opening 17 onto the floor, or into a suitablereceptacle placed under the table for the reception of the finishedproduct 01' the machine.

It will be understood, or course, that as soon as the forming headbegins its receding movement, the jaws 2 are opened by the action of thesprings 12, thus completely freeing the forming head with the piece ofmetal now formed thereon, leaving the piece of metal perfectly free tofall by gravity down through the opening 17 in the table 1 when movedover the same, since the natural resilience of the metal will cause thesame to loosen itself around the forming head.

It the metal to be operated upon proves to be a little refractory, itmay sometimes be found necessary to apply a very powerful clamping forceon the metal just as the clamping operation is completed, and in orderto do this without imposing undue strain on any of the parts of thedevice, I

" -prov'ide the curved slots Tat their inner ends with the angularextensions 18, the parts he- 7 ing so arranged in that instance that thefinal movement of the thrust bar will force the rollers '6 slightly intosaid angular em tensions, which will exert a powerful force on the twojaws pressing them toward each other.

The arrangement of the curved guideways 7 relative to the other parts ofthe device may be somewhat varied according tothe nature of the work tobe performed, but the relatlve arrangement of these guide- Ways as shownin the drawings is as follows :-VVhen the forming dies are closed, aline struck through the centre of the at right angles to the guidewaysbof the fixed member will pass through the centres of the inner ends ofthe curved guideways T, and a similar line struck through the pivot 3 ofthe jaws will pass through the lower ends of said curved uide slots 7 sothat the length of the guideways 7 projected on a base line parallel tothe walls of slot 5 is approximately equal to the travel of the pivotAgain a line passing through the ends of either curved guide slot 7 willbe approximately parallel with said guideway 5.

having; now described my invention, what I claim as new and desire toprotect by Letters Patent is j I V l. in a device ot the characterdescribed, a ired member having a guideway extend ing in. a straightline, and inwardly curved guideways on opposite sides said first namedguideway, all of said guideways e i'zending in the samegeneraldirection; a pair of pivoted tormingjaws having guided movementback and forth, at their pivot point, in said first named guideway, andguided movement between their ends in said curved guideways, saidcooperatingparts being arranged to open the jaws when their pivot pointmoved. toward one end of said first named guidewayand to close them whenit is moved toward the other end thereof: a tiorming head adjacent thepivoted end ot the tormin aws movable in alinement with the first named'uideway into engagement with said forming jaws at their pivoted end andarranged to move said jaws sufficiently to close the jaws around saidforming head. v t

2. In a device of the character described, a fixed member having agliiideway extending in a straight line, and inwardly curved guidewayson opposite sides of said first named 'uideway, all of said guidewaysextending in the same generaldirection: a pair of forming jaws pivotedto each other at one end and having guided movement back and forth attheir pivot point in said first named guidewajn and guided movementbetween their ends in said curved guideways, said cooperating partsbeing arranged to open the jaws when their pivot :point is moved towardone end of said firstnamed g-uideway and to closethem whenvit is movedtoward the other end thereof; yielding means tor noiunally pressing theforming jaws at their ivoted end in the direction in said first namedguideway adapted to open the jaws; a. forming head adjacent the pivotedend of the forming jaws movable back and forth in alinement with thefirst named guideway into and. out of engagement with said forming jawsattheir pivoted'end and arranged to move said jaws close on their pivotand having guided movement back and forth at their pivot point in thefirst named guideway, the centre of the jaws when closed being inalinement with the inner ends of the curved slots and the pivot pointbeing in substantial alinement with their outer ends; and meansapproximately midway between the ends of said jaws for operativeengagement with I said inwardly curved guidew-ays; whereby the jaws willbe opened and closed 'as their pivot point is moved back and forth inits guideway.

4-. A device of the character described, comprising affixed memberhaving a guideway extending in a straight line, a pair of pivoted jawsand a cooperating forming head, the forming head and the jaws at theirpivot point having guided movement relatively to the fixed member, thefixed member also having inwardly curved guide ways on opposite sides ofsaid first named guidewav extending in a general direction substantiallyparallel with said. first named guideway; and projections on the jaws between their ends for engaging said curved guideways, said projectionbeing arranged to come to the inner ends of said curved guideways whenthe aws are closed and to their outer ends when the jaws are open;

whereby the back and forth movement of the pivot of the jaws in thefirst named guideway will open and close the jaws.

in a device of the character described, a fixed member having a guidewayextending in astraight line and inwardly curved guideways on oppositesides of said first named guideway, all of said guideways extending inthe same general direction; a pair of pivoted jaws having guidedmovement back and forth at their pivot point in the first named guidewayand project-ions between their ends taking into said curved guideways,said cooperating parts being arranged. to open the aws when their pivotpoint is moved in one direction and to close them when it is moved inthe other direction, said curved guideways being provided at their innerends with angular extensions adapted to move the intermediateprojections of the jaws still farther toward each other when forced intosaid extensions.

' In testimony whereof I affix my signature.

WILLIAM E. GRAHAM.

